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This paper analyses the task of the modernisation of the start-up processes for steam turbines. The modernisation is aimed to extend the total lifetime. The methodology is presented, which chooses the new start-up conditions with the regard to the actual material wear of the components. The paper describs the range of the conducted research and its results. The choice of the specific optimisation...
In the paper the strength of adhesive joints loaded in raised temperature conditions was researched. Considering the great difficulty with researching of long-term strength by experimental methods, numerical analysis was used to achieve this aim. According to experimental and numerical research, durability of adhesive cement Belzona1111 was tested for the assumed conditions of experiment. There was...
The paper attempts to assess the influence of closed conduits' parameters on maximum pressure values recorded as a result of waterhammer and on the time of keeping unsteady flow with cavitation. A number of numerical tests, necessary for carrying out this research program, were performed using the authors' own programs written in Matlab and based on effective cavitation transient models, which take...
The aim of the study was a correlation between the tribological characteristics of a lubricated ceramic-polymer friction joint and the 3D roughness parameters of ceramic body. The tests of materials in reciprocating motion were performed by means of a pin-on-flat tribotester denoted as T-17. The ceramic plates with various roughness parameters which containing different concentration of ZrO2 and Al2O3...
This paper presents the general description of a lubrication problem for two co-operating living cartilage surfaces separated with a bio-fluid in human joints for unsteady boundary conditions. The synovial bio-fluid has visco-elastic properties. The growth of the tissue is taking into account. The congenial growth strain rates in the synovial fluid and in the cartilage are presented in the described...
The article describes an operation system, which is executed by the transport unit in cooperation with the operator. The purpose of the system is to define tasks concerning the object-directed actions. The scheme of the system was shown and the decisive processes PD1 (action) and PD2 (workspace) were described. Solutions concerning the monitoring of the work space using visual systems and object-positioning...
Until a now, a method for calculating the parameters of a bearing's work has constituted a problem contrary to a construction task. This work has described the adiabatic model of a short floating ring bearing. To solve equations, the following self-imposed parameters have been accepted: bearing load, and rotational speed of a journal. The position of a journal's centre and floating ring bearing has...
This paper presents the diagnostic system utilising artificial neural network ANN for the purpose of the recognition of states in reparable technical objects. The initial diagnostic information is processed by the ANN together with the use of image recognition theory. A general scheme describing the inner structure of the object was developed. Diagnostic analysis was performed and the set of diagnostic...
The paper presents an attempt to evaluate the wear of piston-cylinder assembly with the aid of a vibration signal recorded on spark ignition (SI) engine body. The subject of the study was a four-cylinder combustion engine 1.2 cubic dm. Diagnosing combustion engines with vibration methods is especially difficult, due to the presence of multiple sources of vibration interfering with the symptoms of...
The paper presents some selected calculation results whose purpose is to find the dimensions of the spiral groove on the journal bearing that the load capacity should not be impaired. A three-dimensional oil flow was considered which was described with the Navier-Stokes equations and the equation of energy. The system of equations was solved by applying the finite element method. It is proved that...
A steel working plant is a complex production system where the processes are performed on the continuous basis. The process starts with raw materials: iron ore, carbon, limestone, and others and end with final rolled products. Production scheduling in such complex systems is a formidable task. Research work to date has been restricted to the selected plant departments or processes. Ensuring the continuous,...
The paper presents the results of laboratory and simulation tests of energy efficiency of hydrostatic transmission with volumetric control. The tests were carried out at the test bed built on the basis of PTO type displacement machines and allowed the verification of mathematical models of the loss and energy efficiency of elements and hydrostatic transmission proposed by Z. Paszota.
The dynamic model of a rotating unit of a turbocharger has been designed. Both masses of the rotors and shaft have been modelled as concentrated masses. The rotating unit has been propped on two supports forming lateral sliding bearings with a floating ring bearing. Each bearing is designed including the floating ring bearing mass. The shaft of a rotating unit spins at angular velocity omega1; whereas,...
The article presents the results of the experimental investigation on a bearing with a spiral groove cut on the journal. The presented research results review the theoretical research conducted previously. The results of the investigation on a bearing with a spiral groove on the journal (load capacity, oil temperature, and oil flow rate) were compared with those obtained for a standard bearing with...
The operation and mainenance factors as well as the destructive processes of the technical object elements cause unfavourable changes in the values of the significant functional features causing failures. A damage to a technical object has been defined as exceeding admissible limiting values by significant values of the features describing its elements. Based on the analysed references in question...
The considerations in this paper are orientated towards the relationship between terotechnology and the theory of exploitation. First, the history of the birth and development of exploitation theory in Poland is described, citing the definition of this field of science as well as formulating basic problems considered in the framework of its area. A definition of the term exploitation process is given,...
This publication presents a concept for assessing product quality from the perspective of production process reliability and taking into account operating costs. The stability of a production process can be assured by reducing its sensitivity to the impact of identified sources of variation. This can be done using statistical methods and models. The application of statistical experiments is illustrated...
All accepted and applied strategies concerning the operation of aircraft oblige engineering services to monitor fatigue fractures of aircraft construction. Fatigue fractures belong to a dangerous type of damages. Engineering services are to detect fractures before reaching the admissible length, which is determined by taking flight safety into consideration. Detection of a fracture results in the...
The results of the investigations of the post and exploitation emissions of the harmful components of the fumes of engines from ZS were introduced in the work. Obtained results were subjected to a statistical study according to new computer procedures. Qualitative and quantitative reports were established for the level and kind of emission in reference to the changes of the state of studied engines.
The article presents an attempt at evaluating the state of engine operation under a simulated shortage of fuel inflow to individual cylinders. The object of research was a four-cylinder 1.2 cubic dm capacity combustion engine. The vibration acceleration signals registered on the engine block ZI were assumed the source of information on the engine condition. In case of diagnosing combustion engines...
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